The invention relates to the area of plug-in modules for digital computers, particularly IC memory cards. Typical multipin connectors presently used to connect the circuits of removable cards to a host computer have a number of problems, including unreliable performance under harsh environmental conditions such as temperature extremes, shock, vibration, and contamination. Also, they exhibit excessive wear under repeated insertion/removal cycles, and a limit on addressing capability as a result of the parallel interface using one connector pin per address line.
At present, a large number of Industry Standard memory cards exist, having pin counts of 38, 40, 50, 60, 68, and 88 pins. As the pin count has grown to accommodate larger addressing capability and different IC types, such as DRAM, the connector system has become more expensive, and also has the ergonomic disadvantage of ever higher insertion forces. The ideal connector system would be one which allowed very easy insertion, more like a floppy disk, combined with low cost and high reliability. Although non-contact connectors have been used, incorporating a variety of physical effects, such as capacitive, inductive, and optical, these known devices have disadvantages that restrict their applications, including low data rates, high cost, inadequate power delivery, and bulky physical configurations.
In the above mentioned U.S. Pat. No. 5,229,652, this inventor disclosed a non-contact system for general purpose application to computer modules. This application extends the concepts of U.S. Pat. No. 5,229,652, the disclosure of which is incorporated by reference in this present application, to IC memory cards by the added features discussed in the following Summary of the Invention.